Nutrition evaluation in the male and female participants of the Baltimore Longitudinal Study of Aging (BLSA) has been carried out by periodic collection of 7-day dietary diaries and by measurement of vitamin levels in plasma. The diary technique has provided data over a 35 year period in men and a 15 year period in women. The ages of the participants range from 20 to 95 years. Since the BLSA is a multi-disciplinary study, it is possible to carry out correlations between nutritional intakes and levels and other potentially related variables and outcomes. The results of longitudinal changes in diet (aging and secular effects) over three decades (1960s, 1970s, and 1980s) have been reported. We have re-initiated dietary diary collection for the 1990s by establishing collaborations with USDA and HNRCA scientists (see above). There are no data sets elsewhere on nutritional variables in human beings of comparable duration, reliability, number of subjects, and association with important physiologic and outcome variables. An analysis has been carried out of the intake of three of the B-vitamins (folacin, B12, and B6) in 564 participants over the adult age range. Intake via diet and via supplementary vitamins was quantified. An intake of 2/3 or less of the RDA for each vitamin could be taken as the "at risk" level. Since this population is generally highly educated, upper-middle socio-economic class, and, to some extent at least, health conscious it was surprising that a relatively high percentage fell into the at risk category, especially for B6 intake. In general, although age and sex differences were not large, the younger subjects 20-59 years had a higher percentage at risk than those aged 60-95 years and this was true in men and women. Interestingly, those taking supplemental B-vitamins tended to have higher intakes in their food than those who did not take supplements, i.e., generally those not requiring supplements are the ones who take the additional vitamins.